Updates to the new systemjs

This updates us to the latest systemjs as is merged in bitovi/systemjs.
All tests passing.  One change that is possibly controversial:

SystemJS no longer supports the `__useDefault` option in es6 modules to
import into non-es6 formats as the module's value. Instead any non-es6
module that imports an es6 module can use use it's `default` property.

So instead of:

```js
define(['es6-module'], function(module) {
  // use module
});
```

You have to do:

```js
define(['es6-module'], function(module) {
  var modValue = module.default;
  // Use modValue
});
```